fix: round website rates to two decimals

backend/test_website_client.py

@@ -1,3 +1,5 @@
+from decimal import Decimal
+
 import httpx
 import pytest
 
@@ -5,6 +7,7 @@ from app.services.website_client import (
     WebsiteError,
     _friendly_connection_error,
     _friendly_http_error,
+    calculate_target_rate,
     normalize_groups,
 )
 
@@ -28,8 +31,8 @@ def test_normalize_groups_unwraps_sub2api_paginated_response():
     })
 
     assert [group["id"] for group in groups] == ["codex-free", "my-plus", "deepseek"]
-    assert groups[0]["rate_multiplier"] == "1"
-    assert groups[1]["rate_multiplier"] == "1.5"
+    assert groups[0]["rate_multiplier"] == "1.00"
+    assert groups[1]["rate_multiplier"] == "1.50"
     assert groups[2]["rate_multiplier"] is None
 
 
@@ -45,7 +48,7 @@ def test_normalize_groups_unwraps_wrapped_list_response():
     assert groups == [{
         "id": "default",
         "name": "Default",
-        "rate_multiplier": "2",
+        "rate_multiplier": "2.00",
         "raw": {"id": "default", "name": "Default", "rateMultiplier": "2.0"},
     }]
 
@@ -78,7 +81,43 @@ def test_normalize_groups_keeps_plain_dict_mapping_compatibility():
     })
 
     assert [group["id"] for group in groups] == ["free", "paid"]
-    assert groups[0]["rate_multiplier"] == "1"
+    assert groups[0]["rate_multiplier"] == "1.00"
+
+
+def test_update_group_rate_writes_rounded_two_decimal_number():
+    from app.services.website_client import Sub2ApiWebsiteClient
+
+    requests = []
+
+    def handler(req: httpx.Request) -> httpx.Response:
+        requests.append(req)
+        return httpx.Response(200, json={"ok": True}, request=req)
+
+    client = Sub2ApiWebsiteClient(
+        base_url="https://target.example",
+        api_prefix="/api/v1/admin",
+        auth_type="api_key",
+        auth_config={"key": "admin-key"},
+    )
+    client._client = httpx.Client(transport=httpx.MockTransport(handler))
+
+    try:
+        client.update_group_rate("/groups/{id}", "vip", Decimal("2.2"))
+        client.update_group_rate("/groups/{id}", "free", Decimal("1"))
+        client.update_group_rate("/groups/{id}", "small", Decimal("0.1275"))
+    finally:
+        client.close()
+
+    assert requests[0].url.path == "/api/v1/admin/groups/vip"
+    assert requests[0].read() == b'{"rate_multiplier":2.2}'
+    assert requests[1].url.path == "/api/v1/admin/groups/free"
+    assert requests[1].read() == b'{"rate_multiplier":1.0}'
+    assert requests[2].url.path == "/api/v1/admin/groups/small"
+    assert requests[2].read() == b'{"rate_multiplier":0.13}'
+
+
+def test_calculate_target_rate_rounds_to_two_decimal_places():
+    assert calculate_target_rate(["0.1275"], 0, "max_plus_percent") == Decimal("0.13")
 
 
 # ——— _get_account_ids / account_exists ———